An automotive vehicle door with a window movable between an open and closed position is typically mounted within a pair of glass guides and, in addition, has an upper glass seat, or guide, for receiving the window when in the uppermost, closed position. The glass guides direct the window when moving to an open position, that is, when removed from the upper glass guide from obstructing the window opening, either partially or completely. When completely unobstructing the window opening, the window panel is below a beltline portion of the door, normally the lowermost portion of the window opening adjacent the inner panel and outer panel of the vehicle door. In the completely opened position, the window panel is relatively unaffected by vehicle induced pressure variations inboard and outboard of the vehicle door since the window panel is enclosed therewithin. In the closed position, the edges of the window panel seat with and are stabilized by the rearward, forward, and upper window guide channels. Thus, despite vehicle motion induced pressure variations between the passenger compartment of the vehicle and the outwardly adjacent area of the window panel, as a result of differences in relative air speed therebetween, the window panel remains firmly in place so that vibration, and the concomitant noise, are significantly reduced.
In some vehicle doors, a forward or rearward edge of the window panel may completely disengage from a window guide when the window is partially opened, due to the shape of the window door frame. In such a position, vehicle motion may induce the window panel to vibrate, causing undesirable noise and potentially loosening the window panel, the glass guides, or both. Additionally, in some vehicles, it is desirable to limit the window panel from completely unobstructing the window opening, and the aforementioned problem cannot be remedied by lowering the window panel below the beltline.